All-Altermagnetic Tunnel Junction of RuO2/NiF2/RuO2
Authors
Long Zhang
Guangxin Ni
Xuehao Wu
Guoying Gao
Abstract
Emerging altermagnets offer a promising avenue for spintronics, yet their integration into magnetic tunnel junctions has been hindered by reliance on ferromagnetic electrodes (introducing stray fields) or by limited functionality (non-tunable magnetoresistance without spin filtering). Here, we propose an all-altermagnetic tunnel junction (AAMTJ) paradigm composed exclusively of altermagnets - exemplified by experimentally feasible RuO2/NiF2/RuO2. Giant tunneling magnetoresistances of 11,704%, 2,496% and 1,892%, and high spin-filtering of ~90% are achieved. This architecture unlocks tunable multistate magnetoresistance and spin filtering via magnetization control of the electrodes and barrier, stemming from their synergistic and antagonistic alignments of momentum-dependent altermagnetic spin-splitting. Our AAMTJ inherently exhibits low consumption and zero stray field, with nonrelativistic spin splitting and vanishing magnetic moment, combining the advantages of both ferromagnetic and antiferromagnetic tunnel junctions. This AAMTJ paradigm provides a practically versatile platform to realize the revolutionarily potential of altermagnets for reconfigurable magnetic memory devices.
